Have MIKC* Genes Been Lost During the Evolution of Higher Vascular Plants?
If MIKC*-type genes are really absent from extant ferns and seed plants and are not just awaiting isolation from these taxa, this class of genes must have been lost in the lineage that led to extant ferns (sensu lato) and seed plants; alternatively (but less likely), this class of genes was lost several times independently, e.g., at the base of extant ferns and seed plants. It can be assumed that not many, probably only one, MIKC*-type genes were present in the respective lineage, to make the loss of a complete class of genes a likely event. Even then, it raises the intriguing question as to what function MIKC* genes had and have, so that this gene type was conserved in mosses and clubmosses for about 450 MYA but became dispensable in the “higher” vascular plants.
